Lathe-center.



W. Y. MENTZER.

LATHE CENTER.

APPLICATION FILED MAR. 1. I916.

. Lgwmm. Patented Se'pt, 4,1917.

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UNITED %TATE@ PATENT @FFIQE.

WALTER Y. MENTZER, GRAND RAPIDS, MICHIGAN, ASSIGNOR TO GRAND RAPIDS SCHOOL EQUIPMENT 00., 0F GRAND RAPIDS, MICHIGAN.

LATHE-CENTER.

Specification of Letters Patent.

Patented dept. 4i, I'iid'i.

Application filed March 1, 1916. Serial No. 81,477.

To all whom it may concern:

Be it known that I, WALTER Y. MENTZER, a citizen of the United States, residing at Grand Rapids, county of Kent, State of Michigan, have invented certain new and useful Improvements in Lathe-Centers, of

which the following is a specification.

This invention relates to improvements in lathe centers.

The main object of this invention is to provide an improved lathe center having work engaging spurs with a. guard which normally projects over and protects the spurs and at the same time does not interfere with the engagement of the work with the spindle.

Further objects, and objects relatmg to structural details, will definitely appear from the detailed description to follow.

I accomplish the objects of my invention by the devices and means described in the following specification. The invention is clearl defined and pointed out in the claim.

A structure which is a preferred embodiment of my invention is clearly illustrated in the accompanying drawing, forming a part of this specification, in which:

Figure I is a side elevation of my improved lathe center.

Fig. II is a detail view, partially in central longitudinal section on a line corresponding to line 22 of Figs. I and III, a

piece of work being shown in operative position.

Fig. III is a front end elevation.

In the drawing similar reference characters refer to similar parts throughout the several views, and the sectional views are taken looking in the direction of the little arrows at the ends of the section lines.

Referring to the drawing, the spindle 1 is provided with a center pin 2 and work engaging spurs 3. These spurs are grouped about the center pin, as is common practice. The outer edges of the spurs are preferably curved, as shown in Fig. III, so as to constitute supporting means for the guard sleeve 4:. This guard sleeve 4 is slidably mounted on the spindle, its inner end slidably embracing the collar 5 on the spindle. Its outer end slidably embraces the spurs,

as shown. The guard sleeve is also preferably provided with an internal annular rib 6, which is in sliding engagement with the spindle. This rib 6 constitutes a stop member coacting with the inner ends 7 of the spurs to limit the outward movement of the guard sleeve. When the rib 6 is in en gagement with these shoulders the guard sleeve projects beyond the spurs, as shown in Fig. I.

A coiled spring 8 is arranged within the sleeve between the rib 6 and the collar 5 which serves as a supporting shoulder for the inner end of the spring so that the guard sleeve is urged yieldingly outward. The guard sleeve does not, however, interfere with the engagement of the work with the spurs as it yields when the work is chucked up or forced onto the spurs.

In my improved lathe center it is unlikely that the garments or tools of the operators shall be engaged with the spurs and, as stated, the usual use of the lathe is not interfered with in anyparticular.

My improved lathe center is especially designed by me for use in lathes intended for use in manual training, although it is advantageous in any lathe.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

In a lathe center, the combination of a spindle provided with a center pin and spurs, of a collar on said spindle, a guard sleeve slidable on said collar and having an internal annular rib slidable on said spindle, the inner ends of said spurs constituting stops coacting with said rib to limit the outward movement of said guard sleeve and disposed so that when the stops are engaged the guard sleeve projects over the spurs, and a coiled spring arranged within said guard sleeve between said collar and rib to urge the guard sleeve yieldingly outward.

In witness whereof, I have hereunto set my hand and seal in the presence of two witnesses.

IVALTER Y. MENTZER. [1,. s.]

Witnesses:

Gno. F. REINHARD, W. B. S. MATHESON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Eatenta,

Washington, D. G." 

